Does A Dehumidifier Help With Mold? 

A mold infestation is one of the most common problems homeowners have to deal with. It is an even bigger problem if you live in an area with high humidity levels. They can affect any area of the home especially the walls, floors, and furniture in poorly ventilated areas like the basement, attics, crawlspaces and so on. In some more serious cases, even regular living spaces can be affected by mold growth. Interestingly, a mold infestation isn’t a problem associated with old buildings alone. Experts say installing a dehumidifier is the best solution to manage a mold infestation. Is this true? Does a dehumidifier help with mold? This article answers that question

What is mold?

Does A Dehumidifier Help With Mold? 

A mold is a type of fungus. The term refers to a large and diverse group of fungal species with a fuzzy appearance that causes discoloration on food, fabric, furniture, or walls.

Molds are one of the main microorganisms that cause biodegradation of materials. They are also associated with allergies, asthma and other respiratory disorders.

The common types found in the house include Alternaria, Aspergillus, Chaetomium, Aureobasidium and so on.

Why is mold in the house?

There are various factors that can contribute to the growth of mold in the house, these include PH, light, temperature and most importantly water. High humidity level in the home is one of the most important factors that promote the growth and spread of mold within the house.

They typically grow in damp places with poor ventilation in the home such as bathrooms, attics, inside cabinets, basements or attics.  When leaking pipes, contact with bare ground and other factors cause moisture to form in poorly ventilated areas, mold may begin to grow there with time as the humidity level rises to a level suitable to support their growth.

What humidity level causes mold in the house?

A warm humid condition is an ideal environment for molds to thrive.  Typically, molds need humidity levels of about 70% to thrive although they will still grow and survive at about 55% humidity. Based on these figures it is recommended that you keep humidity level within your home at about 50% or less as this is unfavorable for mold growth.   

Does dehumidifier help with mold?

If you have a mold problem in your home, the most effective way of dealing with it is by installing a dehumidifier. Since high humidity promotes mold growth, reducing the humidity level in your home to about 50% using a dehumidifier will prevent further increase in mold. The existing mold will become inactive and your mold infestation will not get worse for as long as the humidity level stays low.

However, a dehumidifier does not remove the existing mold. It only stops them from growing and spreading. You might still have to remove the mold growth after installing your dehumidifier.

How to pick the best dehumidifier for mold

If you have made the decision to install a dehumidifier in your home to handle your mold problem you need to ensure that you buy one that works perfectly for your needs. Since there are a lot of options to consider, here are some factors that you should consider as a guide to help you make the right choice.

1. Size of the unit and size of your home

To start with, your choice of ideal dehumidifier depends on the extent of the problem at hand. If high humidity and mold growth is a seasonal problem, a portable dehumidifier will work just fine.  But if the problem is more widespread and occurs quite often, then a whole home dehumidifier is more advisable. You should ensure that the size of the unit can match the size of your home. If you have a small space, choosing a large unit might lead to wastage. On the other hand, if you choose a unit that is too small, you might end up overworking it and still the desired result.

2. Capacity (how much water it can remove per day)

This is one of the most notable criteria you should check before you purchase a dehumidifier. How much water a dehumidifier can remove is usually measured in pints or liters and stated by the manufacturer. What you go for depends mostly on how serious the humidity issue you are facing it. In case of a recently flooded house, for example, you will need a powerful unit that can remove a large amount of water within the shortest possible time. If your mold problem is minimal this might not be required.  

3. The efficiency of the unit

The efficiency of a dehumidifier is measured by how much water it is able to remove as a ratio of the power required. This is measured in liters or pints per kilowatt hour and is commonly called the energy factor. The efficiency might not be a serious factor to consider unless you have a serious mold problem due to very high humidity in which case you have to leave the unit on for a very long time. To reduce electricity cost, it is advisable that you go for a unit with high efficiency.

4. Wattage

While this isn’t really a measure of how good a dehumidifier unit is, it helps you to determine how much work the machine will have to do to get the job done. Again, the wattage to go for depends largely on how much work you need to be done.

Before leaving, also check this article on symptoms of low humidity


Installing a dehumidifier does help with managing a mold infestation. By reducing humidity levels to less than 50%, the atmosphere in your home becomes less conducive for mold and their growth is arrested. Even if the infestation is yet to start you can prevent it completely by installing a dehumidifier and others enjoy a lot of other benefits of reduced humidity level.  

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